5) To be or not to be a Passive House?

Originally the plan was to build a Passive House which is a designation requiring a stringent set of design parameters for a minimally intrusive, ecological, ultra-low energy home. The house has to hit an extremely low energy per square foot prerequisite, it has to be airtight, have an air treatment system that includes heat recovery, super-insulation, etc.. A brief overview can be found at Passive House

We decided not to do it. Primarily because the house is in Vermont.. The original Passive House standards came out of Germany where the climate is pretty much benign. But in North America we have extremes. The Green Mountain State can range from 40° below zero in the winter to over 100° in the summer. The U.S. Passive House Institute has tried to deal with the variability of the American climate by creating several climate zones: PHIUS Climate Zones.

But in working with our contractor, we determined that the standards don't make sense for the house we have in mind. For one thing, it limits the square footage of windows, ostensibly so the house doesn't overheat in the summer. That's not a problem in our location. Very few houses even have air-conditioning. What we need is heat. We've designed the house to take maximum advantage of the winter sun, and that means plenty of south-facing windows. Not to mention the views are so great we're loathe to wall them off!

So though we're planning to include systems that meet 90% of the Passive House standards, we're not going to get the certificate.